catgirl/handle.c

185 lines
4.8 KiB
C

/* Copyright (C) 2020 C. McEnroe <june@causal.agency>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include <err.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include "chat.h"
static const char *CapNames[] = {
#define X(name, id) [id##Bit] = name,
ENUM_CAP
#undef X
};
static enum Cap capParse(const char *list) {
enum Cap caps = 0;
while (*list) {
enum Cap cap = 0;
size_t len = strcspn(list, " ");
for (size_t i = 0; i < ARRAY_LEN(CapNames); ++i) {
if (len != strlen(CapNames[i])) continue;
if (strncmp(list, CapNames[i], len)) continue;
cap = 1 << i;
break;
}
caps |= cap;
list += len;
if (*list) list++;
}
return caps;
}
static const char *capList(enum Cap caps) {
static char buf[1024];
buf[0] = '\0';
for (size_t i = 0; i < ARRAY_LEN(CapNames); ++i) {
if (caps & (1 << i)) {
if (buf[0]) strlcat(buf, " ", sizeof(buf));
strlcat(buf, CapNames[i], sizeof(buf));
}
}
return buf;
}
static void set(char **field, const char *value) {
free(*field);
*field = strdup(value);
if (!*field) err(EX_OSERR, "strdup");
}
typedef void Handler(struct Message *msg);
static void require(const struct Message *msg, bool origin, size_t len) {
if (origin && !msg->nick) {
errx(EX_PROTOCOL, "%s missing origin", msg->cmd);
}
for (size_t i = 0; i < len; ++i) {
if (msg->params[i]) continue;
errx(EX_PROTOCOL, "%s missing parameter %zu", msg->cmd, 1 + i);
}
}
static void handleCap(struct Message *msg) {
require(msg, false, 3);
enum Cap caps = capParse(msg->params[2]);
if (!strcmp(msg->params[1], "LS")) {
caps &= ~CapSASL;
ircFormat("CAP REQ :%s\r\n", capList(caps));
} else if (!strcmp(msg->params[1], "ACK")) {
self.caps |= caps;
if (caps & CapSASL) {
ircFormat("AUTHENTICATE %s\r\n", (self.plain ? "PLAIN" : "EXTERNAL"));
}
if (!(self.caps & CapSASL)) ircFormat("CAP END\r\n");
} else if (!strcmp(msg->params[1], "NAK")) {
errx(EX_CONFIG, "server does not support %s", msg->params[2]);
}
}
static void handleAuthenticate(struct Message *msg) {
(void)msg;
if (!self.plain) {
ircFormat("AUTHENTICATE +\r\n");
return;
}
byte buf[299];
size_t len = 1 + strlen(self.plain);
if (sizeof(buf) < len) errx(EX_CONFIG, "SASL PLAIN is too long");
buf[0] = 0;
for (size_t i = 0; self.plain[i]; ++i) {
buf[1 + i] = (self.plain[i] == ':' ? 0 : self.plain[i]);
}
char b64[BASE64_SIZE(sizeof(buf))];
base64(b64, buf, len);
ircFormat("AUTHENTICATE ");
ircSend(b64, BASE64_SIZE(len));
ircFormat("\r\n");
explicit_bzero(b64, sizeof(b64));
explicit_bzero(buf, sizeof(buf));
explicit_bzero(self.plain, strlen(self.plain));
}
static void handleReplyLoggedIn(struct Message *msg) {
(void)msg;
ircFormat("CAP END\r\n");
}
static void handleErrorSASLFail(struct Message *msg) {
require(msg, false, 2);
errx(EX_CONFIG, "%s", msg->params[1]);
}
static void handleReplyWelcome(struct Message *msg) {
require(msg, false, 1);
set(&self.nick, msg->params[0]);
if (self.join) ircFormat("JOIN :%s\r\n", self.join);
}
static void handleReplyISupport(struct Message *msg) {
// TODO: Extract CHANTYPES and PREFIX for future use.
for (size_t i = 1; i < ParamCap; ++i) {
if (!msg->params[i]) break;
char *key = strsep(&msg->params[i], "=");
if (!msg->params[i]) continue;
if (!strcmp(key, "NETWORK")) {
uiFormat(Network, Cold, NULL, "You arrive in %s", msg->params[i]);
}
}
}
static void handleReplyMOTD(struct Message *msg) {
require(msg, false, 2);
char *line = msg->params[1];
if (!strncmp(line, "- ", 2)) line += 2;
uiFormat(Network, Cold, NULL, "%s", line);
}
static const struct Handler {
const char *cmd;
Handler *fn;
} Handlers[] = {
{ "001", handleReplyWelcome },
{ "005", handleReplyISupport },
{ "372", handleReplyMOTD },
{ "900", handleReplyLoggedIn },
{ "904", handleErrorSASLFail },
{ "905", handleErrorSASLFail },
{ "906", handleErrorSASLFail },
{ "AUTHENTICATE", handleAuthenticate },
{ "CAP", handleCap },
};
static int compar(const void *cmd, const void *_handler) {
const struct Handler *handler = _handler;
return strcmp(cmd, handler->cmd);
}
void handle(struct Message msg) {
if (!msg.cmd) return;
const struct Handler *handler = bsearch(
msg.cmd, Handlers, ARRAY_LEN(Handlers), sizeof(*handler), compar
);
if (handler) handler->fn(&msg);
}